Furniture maker (and sometimes designer) here.
I’d agree with many of the above suggestions.
To me, the top two shelves need to continue the pattern (long, shorter, shorter, shortest)
I’d put an asymmetrical arches to support them all, one on each side. Being ruthless, I’d then sack off the tower completely so you have four shelves of varying lengths, all the same width, supported by an asymmetrical arch on each side, connected by ladder frames concealed by the shelves.
Bit like this
But the right way up. Sorry if that’s too much of a departure, or doesn’t hold what you need it to hold.
Also beware that an asymmetrical design with a front and back like yours won’t work if you need to point it the other way in another situation.